Wide area computer networks such as the Internet have grown tremendously in recent years, both in terms of data traffic and popularity. As a result, such wide area networks have grown in popularity as distribution media for digital products. From a commercial perspective, “distribution” includes the two distinct phases of purchase and delivery. Many vendors currently using wide area computer networks for commercial distribution only support the purchase phase online. As used herein, “online” means through a computer network. Typically, current online vendors provide a catalog which is available online and which lists and/or describes products. Customers review the products by browsing the catalog, using a World Wide Web browser for example, and make the purchase by providing payment information, e.g., credit card information. The purchased merchandise is then delivered to the customer off-line, i.e., through distribution channels other than the computer network such as through the mail. Overwhelmingly, the majority of products purchased in this manner are traditional non-digital products, such as books, clothing, and food products. Even digital products, such as computer software, digitized video, and digitized audio is purchased in this manner, with product selection and purchase being made online but the delivery being made conventionally by mailing the digital products to the purchaser on a conventional medium such as floppy diskette, CD-ROM, video cassette, audio tape or audio CD.
In contrast to conventional online purchase-off-line distribution systems, a complete system for the online distribution of digital products, such as digital audio, would provide online support for both the purchase and delivery phases. Such an online distribution system presents a number of special challenges not associated with non-digital products. For example, unauthorized duplication of digital products is of particular concern. With conventional distribution of music on CD and cassette tapes, losses from copyright infringement from illegal copying of music are estimated at about $1 billion worldwide, annually. The susceptibility of digital audio to unauthorized copying, and the ability to create perfect duplicates, raises the specter of even more significant losses to the music industry, and has been the single greatest factor in the music industry's reluctance to make music available for purchase over the Internet. Thus, an online music purchase and distribution system must be demonstratively secure from a large variety of attacks and misuses in order to preserve the music owner's intellectual property rights.
A number of security risks are present in the online distribution of music. First, there is a considerable security risk in simply maintaining digital media products in computer systems connected to public networks such as the Internet for access by consumers. In order to effectively enable purchasers to review and purchase digital products, the products must generally be stored on a computer that is accessible through a computer network. However, given the commercial value of such digital products, whether audio data, video data, or software, such computers would be likely targets of attempted unauthorized access to the digital products. Further, the very presence of an online commerce system is itself an inducement to crackers to attempt to break the security controls of such a system and gain access thereto. Thus, an online distribution system for digital products must be secure from such direct attacks. Further, if the online music distribution system is compromised, it is desirable that the underlying digital product itself be secure against unauthorized copying.
Similarly, the protocols and transmission mechanisms by which an online distribution system delivers digital products to a legitimate purchaser must also be secure, to prevent unauthorized users from intercepting deliveries of the digital products during transit through the network.
Finally, once the digital product has been delivered to a user, the product itself should be secure from unauthorized duplication by the user or by others.
The need for security in such an online distribution system are in conflict with many of the features consumers want in terms of flexibility and ease of use. In particular regard to the purchase of audio data, such as songs and related media (e.g., lyrics, graphics, liner notes which can typically accompany conventional retail forms of audio media), consumers want to be able to sample audio products prior to purchasing. It is desirable for such an online music distribution system to provide some mechanism by which users can play limited portions of songs and view related media without having to purchase the song. In addition, a consumer should be able to pass on preview music to other potential new customers.
Similarly, purchasers of music in traditional forms such as compact disc or cassettes are accustomed to simple, easy to use consumer devices, such as portable compact disc players and cassette tape players. For the successful distribution of music over the Internet, the security requirements must not unduly interfere with consumers' ease of use of the system. A consumer should be able to purchase and playback audio media easily and securely. However, security measures, particularly encryption mechanisms, should make the purchased audio unusable outside of the specific devices and mechanism designed to cooperate with the distribution system.
Similarly, consumers are accustomed to being able to play purchased music anywhere they can carry a CD and CD player. Consumers will expect similar portability when purchasing digital media over the Internet. Accordingly, a desirable online music distribution system should allow a consumer to playback purchased audio not merely on a single computer, but on any platform equipped with an appropriately licensed playback device and the licensee's personal identification.
Additionally, given the very high audio fidelity available today with conventional CD products, audio purchased over the Internet from an online music distribution system must have at least the same level of fidelity, or otherwise consumers will not purchase such products. Thus, any encryption or compression methods used must not induce significant signal loss, or impair playback performance.
Various forms of online payment processing systems are currently available and in use, including credit card and debit card authorization systems. In addition, many new forms of online payment are currently in development and will be developed in the future, including digital cash and micropayments. Accordingly, an online distribution system should not require a single form of payment, or use a proprietary payment processing system. Rather, a desirable online distribution system should be adaptable to integrate with all forms of payment processors. Similarly, many merchants are now providing their own online commerce servers from which they offer and distribute products as the retail vendor of such products. A desirable online distribution system should integrate with any variety of merchant systems.
An online music distribution system should also allow for the recovery of secured digital products by consumers who have lost the identification or other security information (such as an encryption key) required to use their purchases. In addition, independent agencies which police copyright infringements should also be able to recover infringing copies, and identify the creator of such infringements.